Treaty Research

This guide describes resources and methods for locating and updating treaties of the United States and other countries.

Status Information for Multilateral Treaties

Once you have located the text of a multilateral treaty, you will need to determine its current status.  On what date did the treaty enter into force?  Which countries are state parties to the treaty?  Have any countries ratified the treaty subject to one or more declarations or reservations?  Have there been any subsequent amendments or supplements (often referred to as protocols) to the treaty text?

The best place to look for status information is the depositary institution for the treaty in question.  The depositary acts as the custodian of the treaty text and also maintains a current record of all state parties to the treaty and any reservations or declarations made by each state party.   Multilateral treaties usually designate an international organization, the Secretary-General of the United Nations or (less frequently) a national government to serve as the depositary.

Depositaries for Multilateral Treaties

  • Multilateral Treaties Deposited with the Secretary-General (MTDSG).
    MTDSG is the most comprehensive resource for updating the status of multilateral treaties.  It covers more than 560 treaties that have entered into force from 1946-present.  The Secretary-General of the United Nations serves as the official depositary for each of these treaties.

    Treaties are arranged chronologically by subject, with each chapter of the MTDSG corresponding to a particular subject.  Note that protocols (supplements) to treaties are listed separately.  To locate a treaty record, click on the relevant chapter to browse or search by title for the name of the treaty.  Each record contains:
    • Basic Information about the treaty, including:
      • Its date of entry into force.
      • The current number of signatories and state parties.
      • The volume number of the U.N. Treaty Series in which the text of the treaty is published.
      • A link to download the text of the treaty in PDF format.
    • An alphabetical list of participating countries, including dates of signature and dates of ratification, accession, and succession;
    • The full texts of all declarations, reservations, and objections made by each state party.
  • Intergovernmental Organizations That Serve as Treaty Depositaries
    The intergovernmental organizations listed below serve as depositaries for multilateral treaties that pertain to a particular subject matter or a group of related subjects.
  • Regional Intergovernmental Organizations That Serve as Treaty Depositaries.
    The following regional inter-governmental organizations serve as treaty depositaries for multilateral treaties drafted under their auspices.  Their respective treaty websites provide regularly updated status information.
    • African Union Treaties
      Includes more than 60 multilateral treaties drafted by the African Union and its predecessor, the Organization of African Unity (OAU), covering human rights and other subjects.
    • Council of Europe Treaties
      Includes more than 200 multilateral Council of Europe treaties covering a wide variety of subjects ranging from cultural protection to cross-border legal cooperation and human rights.
    • Organization of American States Treaties
      Includes dozens of multilateral treaties concluded among countries in the Western Hemisphere on a wide range of subjects.
  • Directory of Treaty Depositary Websites
    The U.S. State Department publication Treaties in Force (TIF) is a good source for identifying treaty depositaries.  For each multilateral treaty to which the U.S. is a party, TIF usually identifies the designated depositary and provides a link to its website (if available).  In addition, TIF includes a directory of depositary websites, which includes many of the most important institutional and national treaty depositaries.  The directory is located in Section 2 of the current (2020) edition of Treaties in Force at page iv.